Reassign - reassign transform for STFT

class audioflux.Reassign(radix2_exp=12, samplate=32000, window_type=WindowType.HANN, slide_length=None, re_type=ReassignType.ALL, thresh=0.001, is_padding=False)

Reassign - reassign transform for STFT

Parameters
radix2_exp: int

fft_length=2**radix2_exp

samplate: int

Sampling rate of the incoming audio

window_type: WindowType

Window type for each frame.

See: type.WindowType

slide_length: int or None

Window sliding length.

re_type: ReassignType

Reassign type

thresh: float

thresh

is_padding: bool

Whether to use padding

See also

Synsq
WSST

Examples

Read 220Hz audio data

>>> import audioflux as af
>>> audio_path = af.utils.sample_path('220')
>>> audio_arr, sr = af.read(audio_path)

Create Reassign object

>>> from audioflux.type import ReassignType, WindowType
>>> obj = af.Reassign(radix2_exp=12, samplate=sr, window_type=WindowType.HANN,
>>>                   slide_length=None, re_type=ReassignType.ALL)

Extract spectrogram

>>> import numpy as np
>>> re_spec_arr, bft_spec_arr = obj.reassign(audio_arr)
>>> re_spec_arr = np.abs(re_spec_arr)
>>> bft_spec_arr = np.abs(bft_spec_arr)

Show spectrogram plot

>>> import matplotlib.pyplot as plt
>>> from audioflux.display import fill_spec
>>> audio_len = audio_arr.shape[-1]
>>> # Show BFT/STFT Spectrogram
>>> fig, ax = plt.subplots()
>>> img = fill_spec(bft_spec_arr, axes=ax,
>>>                 x_coords=obj.x_coords(audio_len),
>>>                 y_coords=obj.y_coords(),
>>>                 x_axis='time', y_axis='log',
>>>                 title='BFT/STFT Spectrogram')
>>> fig.colorbar(img, ax=ax)
>>>
>>> # Show Reassign Spectrogram
>>> fig, ax = plt.subplots()
>>> img = fill_spec(re_spec_arr, axes=ax,
>>>                 x_coords=obj.x_coords(audio_len),
>>>                 y_coords=obj.y_coords(),
>>>                 x_axis='time', y_axis='log',
>>>                 title='Reassign Spectrogram')
>>> fig.colorbar(img, ax=ax)
../_images/reassign-1_00.png
../_images/reassign-1_01.png

Methods

cal_time_length(data_length)

Calculate the length of a frame from audio data.

reassign(data_arr[, result_type])

Get reassign matrix

set_order(order)

Set order

set_result_type(result_type)

Set result type.

x_coords(data_length)

Get the X-axis coordinate

y_coords()

Get the Y-axis coordinate
cal_time_length(data_length)

Calculate the length of a frame from audio data.

Parameters
data_length: int

The length of the data to be calculated.

Returns
out: int
set_result_type(result_type)

Set result type.

Parameters
result_type: int, 0 or 1

  • If 0, then the result is a matrix of complex numbers.

  • If 1, then the result is a matrix of real numbers.

set_order(order)

Set order

Parameters
order: int

order >= 1

reassign(data_arr, result_type=0)

Get reassign matrix

Parameters
data_arr: np.ndarray [shape=(…, n)]

Input audio data

result_type: int, 0 or 1

  • If 0, then the result is a matrix of complex numbers.

  • If 1, then the result is a matrix of real numbers.

Returns
m_arr1: np.ndarray [shape=(…, fre, time), dtype=(np.complex or np.float32)]

The matrix of reassign

m_arr2: np.ndarray [shape=(…, fre, time), dtype=np.complex]

The matrix of origin(BFT/STFT)

y_coords()

Get the Y-axis coordinate

Returns
out: np.ndarray [shape=(fre,)]
x_coords(data_length)

Get the X-axis coordinate

Parameters
data_length: int

The length of the data to be calculated.

Returns
out: np.ndarray [shape=(time,)]